The effect of embryo catheter loading technique on pregnancy rate.

Embryo transfer is the most emotional part for patients during fertilization treatment. Over the last decade, the embryo transfer procedure has undergone numerous changes in the guidelines in order to increase pregnancy rates. One such procedure is the loading of the embryo into the catheter, a thin tube that helps us transfer embryo into the uterine cavity.

Cryopreservation Does Not Affect the Clinical Pregnancy Rate of Blastocysts Derived from Vitrified Oocytes.

Vitrified, or "frozen", donor eggs can either be fertilized and cultured for fresh transfer (group 1), or fertilized and cryopreserved for transfer in a "frozen embryo transfer" cycle (group 2). This study compared the pregnancy rates between the two groups. Frozen donor egg cycles (N = 1213) were analyzed at the World Egg Bank.

Natural cycle IVF reduces the risk of low birthweight infants compared with conventional stimulated IVF.

Study Question: Are perinatal outcomes improved in singleton pregnancies resulting from fresh embryo transfers performed following unstimulated/natural cycle IVF (NCIVF) compared with stimulated IVF?

Summary Answer: Infants conceived by unstimulated/NCIVF have a lower risk of being low birthweight than infants conceived by stimulated IVF; however, this risk did not remain significant after adjusting for gestation age.

What Is Already Known: Previous studies have shown that infants born after modified NCIVF have a higher average birthweight and are less likely to be low birthweight than those infants conceived with conventional stimulated IVF.

Study Design, Size And Duration: Retrospective cohort study of singleton live births in non-smoking women undergoing fresh IVF-embryo transfer cycles from 2007 to 2013 in a single IVF center.

Utilization and success rates of unstimulated in vitro fertilization in the United States: an analysis of the Society for Assisted Reproductive Technology database.

Objective: To examine the utilization and outcomes of natural cycle (unstimulated) IVF as reported to the Society of Assisted Reproductive Technology (SART) in 2006 and 2007.

Design: Retrospective analysis.

Setting: Dataset analysis from the SART Clinical Outcome Reporting System national database.

Placental growth factor is a potent vasodilator of rat and human resistance arteries.

The objectives of this study were to determine whether placental growth factor (PlGF) exerts a vasodilatory effect on rat uterine vessels (arcuate arteries and veins) and to examine regional differences in reactivity by comparing these responses to those of comparably sized mesenteric vessels. We also sought to examine and compare its effects on human uterine and subcutaneous vessels. All vessels were studied in vitro, under pressurized (rat) or isometric wire-mounted (human) conditions, and exposed to a range of PlGF concentrations.

Effects of h1-calponin ablation on the contractile properties of bladder versus vascular smooth muscle in mice lacking SM-B myosin.

The functional significance of smooth muscle-specific h1-calponin up-regulation in the smooth muscle contractility of SM-B null mice was studied by generating double knockout mice lacking both h1-calponin and SM-B myosin. The double knockout mice appear healthy, reproduce well and do not show any smooth muscle pathology. Loss of h1-calponin in the SM-B null mice bladder resulted in increased maximal shortening velocity (V(max)) and steady-state force generation.

Mechanism of VEGF-induced uterine venous hyperpermeability.

Background: Transfer of molecular signals from veins to adjacent arteries is an established mechanism of vascular communication in the uterine circulation, which ultimately depends on venous permeability. This study tests the hypotheses that: (1) uterine veins are permeable to intravenous solutes, using a 3-kDa dextran tracer and (2) this permeability is enhanced in response to vascular endothelial growth factor (VEGF). Additionally, the involvement of nitric oxide (NO), calcium, and the phospholipase C-protein kinase C (PLC-PKC) cascade in VEGF-enhanced permeability were investigated, and the impact of pregnancy-induced uterine vascular remodeling on permeability was evaluated.

Venoarterial communication as a mechanism for localized signaling in the rat uterine circulation.

Objective: Venoarterial communication describes the phenomenon whereby molecular signals in a vein directly influence an adjacent artery. The objective of this study was to investigate, in vitro, the existence of such a pathway in the uterine circulation of the rat.

Study Design: Paired uterine vessels from late pregnant and virgin rats were pressurized and studied in a dual-perfusion vasograph.

Structural remodeling of rat uterine veins in pregnancy.

Objective: This study characterized the cellular remodeling that contributes to uterine venous growth during gestation and evaluated the effect of pregnancy on the mechanical properties of the uterine vein.

Study Design: Diameter and distensibility were calculated in pressurized uterine veins from virgin and pregnant (19-20 days of gestation) rats; the rates of cellular division (endothelial, vascular smooth muscle) were quantified with an intraperitoneal bromodeoxyuridine injection and immunohistochemistry. Elastin content, adrenergic nerve density, and wall thickness were determined in fixed uterine veins and quantified with an imaging program.